Statistical Analysis of Flame Oscillation Characterization of Oxy-Fuel in Heavy Oil Boiler Using OH Planar Laser-Induced Fluorescence

Abstract

e present work investigated the flame structures and oscillations of oxy-fuel combustions in a heavy oil boiler using OH planar laser-induced fluorescence imaging. Combustion instabilities, such as flame oscillation and combustion fluctuation, can assess the performance of an industrial burner in the boiler. e peak position variation in OH concentration was associated with the change of the reaction zone that corresponded with the fluctuation of the heat-release zone in the combustion chamber, which provides a valuable reference for the design of the combustion chamber. e experimental results suggest that the phenomenon of stratified flame combustion is related to the characteristic of flame oscillation. e substitution of N 2 with CO 2 will not significantly influence the flame oscillation frequency but increases the number of flame surface. As O 2 concentration increased in the O 2 /CO 2 atmosphere, the phenomenon of stratified flame combustion disappeared, and the flame presented an island-like structure. e bimodal oscillation of the combustion center was demonstrated by means of the probability density method; CO 2 played a role in the extension of the combustion center. e combustion fluctuation of inner regions was quantitatively described; CO 2 could maintain interregional stabilization to some extent. Compared with traditional measurement methods, PLIF technology has great advantages in evaluating burner performance and optimizing the design of the combustion chamber.